Studies have consistently shown an association between mental health disorders and alcohol use disorders (AUD) during adolescence. In particular, the comorbidity of AUD with Major Depressive Disorder (MDD) is well established and associated with a range of negative outcomes including longer and more severe episodes of illness and greater psychosocial impairment including behavior disturbance. This population may be even more challenging to treat than their adult counterparts because adolescents with MDD/AUD so often have other externalizing disorders besides AUD. Treatment research for this population is quite limited and Healthy People 2020 Objective MHMD HP 2020-14 directly addresses this area: increase the proportion of persons with co-occurring substance abuse and mental disorders who receive treatment for both disorders. The purpose of this application is to conduct a randomized clinical trial comparing Cognitive Behavioral Therapy - Integrated (CBT- I) for adolescents with MDD and AUD to standard care (SC), i.e. an eclectic mix of therapy techniques. A two group randomized design will be used to test the primary hypothesis that the integrated CBT- I protocol designed to treat adolescents aged 12 to 18 years with AUD/ MDD will produce better treatment outcomes compared to standard care with respect to 1) heavy volume alcohol use/ alcohol problems which can contribute to both depression and externalizing behaviors, the most severe of which result in costly residential placements and arrests/incarceration; and 2) depression and suicidal events, the latter potentially requiring expensive Emergency Department visits and inpatient psychiatric hospitalizations. Both the integrated CBT-I and SC condition will be delivered by licensed mental health counselors at a community mental health clinic that uses an Intensive Outpatient Program model to treat adolescents with AUD and mental health disorders who have failed prior outpatient therapy and require more intensive services. Clinicians in the CBT-I condition will receive weekly supervision that focuses on use of the CBT-I protocol. Clinicians in SC will be provided standard clinic supervision that is more eclectic in nature, consistent with typical community care. Outcome data will be collected at one year post treatment. Successful completion of the project aims could change how services are delivered to this high risk group. Its clinical significance lies in ts addressing a critical barrier to the field: how to treat MDD/AUD adolescents.